x,a,y,b=map(int,input().split())
p={}
d=2
while d*d<=x:
  while x%d==0:
    x//=d
    if d not in p:
      p[d]=1
    else:
      p[d]+=1
  d+=1
q={}
d=2
while d*d<=y:
  while y%d==0:
    y//=d
    if d not in q:
      q[d]=1
    else:
      q[d]+=1
  d+=1
if x>1:
  p[x]=1
if y>1:
  q[y]=1
for d,cnt in q.items():
  if d in p:
    k=p[d]*a
  else:
    k=0
  if k<cnt*b:
    print('No')
    exit(0)
print('Yes')